Yuuji, the main protagonist of the story, is just an average high school student. However, his world is turned upside down when he discovers that he is already dead and does not have much time before he disappears. Fortunately, Yuuji is a Mystes who contains a treasure known as the "Midnight Lost Child" (Reiji Maigo). Unlike normal torches, the treasure inside him restores his Power of Existence every night at midnight.